Moving with a quiet intensity that accrues momentum, Afghan director Siddiq Barmak's Osama traps you in a quicksand pull, slowly sucking you into its world until it's too late to escape unscathed. Barmak's snapshot study of life under the Taliban combines documentary immediacy with the calculated eye of the biased observer. For better and worse, he's terrifyingly successful. At Osama's close, that elephant weight sitting on your chest is the knowledge that its world is probably still how many women endure life.

Yes, endure: Mother (Zubaida Sahar), her husband killed in war, loses her hospital position when the Taliban closes the facility; she and her preadolescent daughter (Marina Golbahari) flee with patients and families, helping one man transport his father home in return for his escort back to theirs. Unescorted women are not allowed in public, and in an early scene where the man bikes the mother and daughter home, Barmak poignantly captures day-to-day lives under thinly veiled fear. The mother rides sidesaddle, her foot slightly exposed with her chador pulled up slightly to keep it out of the spokes. The bike comes to a stop, and as an off-screen Taliban guard interrogates the man about why he's allowing his "wife" -- the arrest-avoiding ruse -- to show her legs, the chador creeps down over her feet. It's a loaded, innocuous moment: Women are constantly reminded of their social position.

Without an income-producing man in the family, the mother cuts her daughter's hair, puts her in her dead husband's clothing and passes her off as her son. The daughter now escorts the mother to patients. The daughter works at a merchant's store. And the daughter gets recruited into the Taliban when it corrals for enlistment all boys of age. Her only ally is a street-smart Espandi (Arif Herati), who recognizes her and dubs her Osama after other boys tease her about being too girlish.

The ruse can't last  and then Osama's true unpleasantness begins. What's distressingly effective is how understatedly Barmak plays his drama throughout. This tale could easily play as pure manipulation  comfortably liberal, righteously indignant Americans are Osama's ideal audience  but it never aims for too operatic a note. The deliberate normalcy  where betrothed teen girls are invited to pick the lock that will imprison them, where a stoning is just another event in a day  is a white-hot iron burning Osama into the skin.